Hi all. This is a proposal and realization of new NBD meta context: qemu.
New possible queries will look like: qemu:dirty-bitmap:<export-bitmap-name> Mapping from export-bitmap-name to BdrvDirtyBitmap is done through qmp command nbd-server-add-bitmap. For now, only one bitmap export is allowed per NBD export, however it may be easily improved if needed (we don't have such cases for now) Client and testing. I wrote client code for Virtuozzo, but it turned out to be unused, actually it's used only for tests. We don't have cases, where we need to import dirty bitmap through qemu nbd-client. All this done for exporting dirty bitmaps to the third tool. So, I think, it is not worth refactoring, rebasing and merging client part upstream, if there are no real usage cases. v5: 02: fix nbd_check_meta_export s/client->exp/client->export_meta.exp 04: improve bitmap_to_extents and handle NBD_CMD_FLAG_REQ_ONE correctly v4: 01: add trace for -skipped case 02: new 03: trace -skipped case in nbd_meta_pattern, rebase on 02 04: fix nbd_meta_qemu_query: use meta->exp instead of client->exp, rebase on 02 v3: 01: new 02: rewritten to satisfy changes in 03, drop r-b 03: - fix comments - rewrite nbd_meta_bitmap_query() and rename it to nbd_meta_qemu_query(): parse 'qemu:dirty-bitmaps:' for LIST option to represent list of all dirty-bitmap contexts. - trace points - s/512/BDRV_SECTOR_SIZE/ drop TODO comment 04: s/2.13/3.0 05: new v2: 01 from v1 is dropped: actually, we don't need generic namespace parsing for now (especially, after moving to qemu: namespace, which has the same length as base:), lets postpone it. 01: Improve comment wording (Eric), add Eric's r-b 02: improve commit message move NBD_STATE_DIRTY to header add comment on NBD_MAX_BITMAP_EXTENTS remove MAX_EXTENT_LENGTH and instead update add_extents() which uses it use export_bitmap_context instead of export_bitmap_name to reduce operations on it move from qemu-dirty-bitmap to qemu:dirty-bitmap other way to parse namespace name handle FLAG_DF 03: Improve specification of new qmp command (Eric) Vladimir Sementsov-Ogievskiy (6): nbd/server: fix trace nbd/server: refactor NBDExportMetaContexts nbd/server: add nbd_meta_empty_or_pattern helper nbd/server: implement dirty bitmap export qapi: new qmp command nbd-server-add-bitmap docs/interop: add nbd.txt docs/interop/nbd.txt | 37 ++++++ qapi/block.json | 23 ++++ include/block/nbd.h | 6 + blockdev-nbd.c | 23 ++++ nbd/server.c | 353 +++++++++++++++++++++++++++++++++++++++++++++------ MAINTAINERS | 1 + 6 files changed, 402 insertions(+), 41 deletions(-) create mode 100644 docs/interop/nbd.txt -- 2.11.1